Calculating-dividers.



J. W. MOONEY.

CALCULATING DIVIDERS. APPLICATION FILED, LUNE 5. 191s.

Patented Apr. 8,1919.'

\ "To all 'whom t Mag/concern:

\ Be it known that I,L JosnrH W.:Moonnr,a citizen of the United l'States kofiAJmeIica, a resident of the ycityof St.y Louis, State? of Missouri, have Y invented certain new andy useful Improvements,` iin k GalculatingeDL' viders, of which the following isja'l full, clear, and exactdescription, referencebbeing had to the accompanying drawing, forming lo i -a part ofthis,sp'ecication.v ,i sV Y y This-invention relates to improvements'in calculating dividers',y and more particularly to an instrument adapted for' use?incalcula-- tions involving ratioand proportion,"such.

for example as 6-is to 3 as@ is to w. It will,I

of course, be understoodY that thisV is merely an illustration of a "veryfsimpleexample,

and that thel greatest value 'of .thenf'ewdevice lies fin similar calculations"whereinthev problem is rendered more ditlcult on accountV of Ifractions, or 'byreasonof upeculiar dien. ences Abetween the-*termsxof theproble1n.v `The system of calculation'is ysimilar-tofthey rule of three?? in arithmetic, the three known terms as well as the rmissin'gone'being proportional. 1-

Problems lof y thisl arise in the work of printers, engravers andv others engaged in similar="industries, wherein drawings, printedmatter, and L,the

like, are reducedifor enlarged.'y such cases, the two' importantdimen'sions Lof thel drawing, or thelike, are known`;-one of the n dimensions of the enlargement or'reduction is also known, audit isk neces'sary'tolprede-L terminethe other; dimension. YFor example,

y it a drawing 6- inches X22 inches is' to'- be reduced by photography sofastov make aV cut 3 inches long, it maybe I iecessaryy vfor or more of many persons, including-the cuSfk atomen, an estimatorin thefngravn-g Qt (1 `vertisiug department whemthe c ctvsto be used, and a printer who -Inu'st set typetto., u

much timek and laboris spent in'solving oom-' as is frequently? the'case by'aperson una?, miliar with a short'v method offobtaining the missing dimension.

Therefore, the main whereby` problemsA in4 proportion canbe Y robjeta pfui@ present invention is to produce a simple instrument f arithmetic.

example;thefcharacter 9`535may yindicate' `,that

graphed 'f without vf changing the .location of .the'camera `relativetothe;holderizlfor*the `y a drawings. f On the.- :calculating instrument, J

:th-esef arbitrary; characters, preferably nuf after one ot the; characters has beenfsevdrawings bearing thev `same number can-be n l Patented Apes/1919. Alpncationmed'zrune 5,1918.f'senarnmzaaaas. l 1 v f A1anjoriginaldrawingzisto'be reduced" to" onef, Y i hal-fof-the original -y scale,`and 'if thephotog-f` .tu '4 rv"raphenhasi "ahumbei' .of :drawings lmarked w for a 92 reduction',,theyfcan 'all-be hoto` Yj voV s easily selectedI by .the photographerA and. rfforerfly iihot'srdpli'd Without Cha'sing i the :position` of A thefcopy holder,` rela tive-'ltdv f iugm its, M0151' @t pian' iviewiimgffating, an pbjectftofbe'measured, and showingthe y .Y vcalculating'ldividers inl their primary'l andlazf secondary measuringfpositions. V

e Fig; `'Ily l'isi' an enlarged transversV section `illustrating*the "pivotal connection between'v the rule and-ione' of the legs of' the dividers.l

'-f ing'. m isY an connection." .i y Fig'. I showsjan "and.vv also illustrates the dividersin-twodfl a'f-secondary measuring position, The ele- @alargarl ,pian `viw of the, r n

obiectjtoffbe'flneasured, e as vferent positions one of whichy maybe termed primary measuring positionyand vvthe other fj- 1 longitudinal slot E "formed in the' leg' A for f the recptioaof@pivotpirfrwheretyithe l lpivot pin can, therefore, b e adjusted longi- 4tudinally ofthe slot and in a line radial to the main pivot C whereby the legs are connected together. The rule R can be easily adjusted along the leg A, and it can also be turned on the axis of the pivot F.

'f The rule R is preferably provided with a longitudinal slot, and preferably graduated on opposite sides of the slot to indicate inches land? agate lines, respectively, as shown mostclearly in Fig. I. The legs A'and B are provided with arbitrary gradu'ations indicating various arbitrary points on the radial lines A and B and these graduations may be viewedV through the longitudinal slot in the rule R. In the drawings, I have shown graduations in the form of numerals 11toV 16 onthe legs A and B, but `it is to be understood thatV any other suitableV characters may be used to indicate various points onthe radial lines, and'it is notnecessary for these points to be spaced in any particular manner. It is important, however, to observe that the arbitrary graduations on one leg correspond to the graduations on the other leg, and whenrthe rule R registers with corresponding graduations, it will lie at a rightxangle to a radial' line H drawn from thepivot Gand located midwaybetween the radial'lines A" and' B. In'Fig. I, the graduations 9 on the legs A 'and B ycan be seen Vthrough the slot in the rule R, and it will be apparent thatthe rule R can be adjusted longitudinally of the legs sov as to register with other graduations along the radial lines, and whenever the rule registers with corresponding graduations on the different legs, it will lie at a right angle to the radial Vline H.

The rule R is used to measure distances between the radial lines-A and B at various ,distances from thel axis lof the pivot C, and

Y the graduations on therule begin at theA axis ofthe pivot F which always lies in the radial line A Assuming that the drawing or other object to be reduced by photography measures 6 x2, ,asshown in FigfI, and that the length of the reducedV object is to be 3 inches, :the instrument can be used to, determine the width of the reduced object. A

Thsprobem may be written- ,j 6' isy to 3 as'2v is to w. "Otherwisestated, the user knows the length and width of the original drawing and one of the dimensions of the reduced copy, and by properly using the instrument he can readily determine the other dimension of the reduced copy. The dividers are first positioned as shown at the lower portion of Fig. I, the measuring points D being spaced apart 6 inches, the length of the 0bject to be reduced. The user knows that this 6 inch .measurement is tovbe reduced to 3 inches, so he slides the rule R along` the legs ofthe dividers to a position where the rule will indicate the 3 inch measurement between the radial lines A and B. When the rule is in this position it registers with the graduations 9 on the legs of the dividers, and itliesat a right angle to the radial line H.

The next step consists in moving the dividers to the secondary lneasuring position `shown at the right hand side of Fig. I, moving their legs together so as to measure the 2 inch width at the points D. Although the legs are moved toward each other, the rule R must register with the graduations 9 which were selected in the first measuring operation, Aand said rule must also lie at a rightfangle tothe radial line H. The operator then observes the measurement indicated by the rule, and in this case he finds it to be one inch. This measurement is the result of the calculation, and the width of the reduced copy will be l inch. In other words, 6 is to 3 as 2 is to l.

No matter how complex the three given terms may be, the fourth can be readily ascertained by using the calculatinginst'rument as herein pointed out.

During the primary measuring operation, illustrated at the lower portion of Fig. I, the rule R is positioned on the radial lines A A`and B to establish a definite proportional relation between the rule and the measuring points D, and this'relation is indicated bythe arbitrary character 9. Hence, whenever the rule properly registers with the characters 9, it will cooperate with the measuring points D to maintain the proportional relation as (iV is tov 3. The arbitrary characters enable the rule to be properly positioned for thesecondary measuring operation, and

in changing from one measuring position to another, the rule must turn on the axis of its pivot F, but this does not affect the accuracy of the device, for the axis of the pivot is locatedk on thel radial line 'A'.

In' addition to serving as a guide for posi- .tioning the rule R, the arbitrary characters can be advantageously used to indicate deflnite proportional reductions. For example, in the' illustration herein given, the character 9 is selected during the primary measuring operation, and the samev character will be selected lwhenever the reduction is as 6 to 3, and, if the photographer is given a number of drawings eachjifmarked for av9 reduction, he will understand that allv of these drawings canY be photograplied;with-V 'i out changing the location f the copy holder relative to thecamera, e

I claim: y

on one of said legs/and guided "in a radial line drawn from the point of'rthe'legftothe rst mentioned, pivot, the other `leg""having a longitudinal .measuring line formed in alinement rwith lits pointed end and` the lrst mentioned pivt,fa rule spanning said. legsV and pivotally secured at one end to said rulef f pivot so that the fr'ule can be yreadily/ adjusty ya0 Vturned on saidfrule-pivotv to lproperly yIneasure distances between the radial lines, and

' said legs being provided withfcorresponding oppositely disposed 'arbitrary Tgradilation s indicating various arbitrary `points v on the radial lines of theilegs so thatftherule can be readily positioned at anrightl angle `to a radial line bisecting'` the `angle between ltli'e" aforesaid radial lines.V j y Y 2. Calculating dividersr comprisingy apair of legs,a pivot connecting saidjlegs, the free' vend of each leg being pointedinafradial line drawn fromfthe centerLof the pivot,

oneef said. legs 'being provided witha lon-I gitudinal ,slotl formed inthe ,radial line leading from the pivot to its 'pointed freek end, the other leg having -a long itudinal.rau dial measuring line formed alineme'nt with its pointed end and the-pivona rulepivot adjustably lmounted in-saidj longitunal slot so that it can` be adjusted in a line radial to the first Vvmentioned pivot, ruleV spanning said legs -andpivotally secured at one yend to said rula-pivo tl so'that their/ule can be readily adjusted longitudinally of f the legs and readily positioned` to measure distances between the radiallines, said rule i being provided with a longitudinal slot andi n Copies of thisv patent mayube olitanedfo indicate inches and" agate lines "respectively,

graduations indicating various arbitrary` nal slot in"k the rule, the arbitrary Agradllathey rule can be VVreadily positioned in .a line at a. right `angle to'an imaginary radial `line y1bise ;ting the angle between theA aforesaid radial lines'.

pointir'i "aradia'l' line drawn fromy thefoenter Y' points on the radial lines of the legs and ars Y-; ranged to be viewedithrough thelongitudi'- jy; i j! v1 tionsfk on `one leg correspondingto ythe ,arbi-r xtraryjgraduationsfon lthe other leg so that ,y

3;'Calculating dividers comprising'a pair 1 fof legs; aipivoteonnecting saidv legs, the A ffreeend'of each leg having `-a measuring i. 7

65 f lof said pivotga transverseV rule mounted on. p A one'L-fsa'id legs andfadjustableek longitudi ed longitudinallylof the legs Fand readily-1 can be` used 'tot measure distances between maryv rneasuringgpositions wherein the legs V'andlruleaije positioned forjknown propor- Y tionalL measurements, 'and also freerto ocg cupyfs'ee'ondaiy' measuring positions where-1 f "in theL legs are @positioned for a known@ measurement while the rule is positioned to` v f indicate the result of the calculatiom'and ;the legs b eingp'rovidedwith meansx whereby the secondary position lof the rule is indi# 'Y catedwbeni the parts occupy their primaryl i measuring positions, said means including corresponding oppositely disposed varbitrary graduati ons indicating rvarious points alongu the'ljegs so asv to indicatethe 'secondary pof 'erentspoints in, said .radial lines, so that the .rulelwillfindicate distances from the radial line of leef In testimony hereunto ax; 'my' signature. w t 'JOSEPH W MOONEY.

one leg tov the radial line ofthe other that i lClaim the foreggiiig I Vsition;ofthejrule 'whilefthe latteris locatedV i i* inits,- primary measuring position, and said u graduations being formedto indicate; diff4 v 99. V t

n; velcent's caen, byilaedrcssingthe 4,(tomn'xssioxier lofiihetents, t 'i ,y Washingtomn. y 7 

